Home network of connected consumer devices

ABSTRACT

A method of generating a representation of a structure includes providing an ad hoc mesh network having at least two nodes associated with the structure, obtaining time of flight data for each node in the network, and using the time of flight data to generate the representation of the structure. A method of generating a three-dimensional representation of a structure includes providing an ad hoc mesh network having at least three nodes associated with the structure, wherein at least one node is a mobile node that moves around the structure, obtaining time of flight data for each pair of nodes in the network, and using the time of flight data to generate the three-dimensional representation of the structure.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is related to the following copending US PatentApplications, which are incorporated by reference herein in theirentirety:

U.S. patent application Ser. No. 13/551,539, “Home Network of ConnectedConsumer Devices,” filed Jul. 17, 2012.

U.S. patent application Ser. No. 13/551,546, “Home Network of ConnectedConsumer Devices,” filed Jul. 17, 2012.

U.S. patent application Ser. No. 13/551,551, “Home Network of ConnectedConsumer Devices,” filed Jul. 17, 2012.

U.S. patent application Ser. No. 13/551,558, “Home Network of ConnectedConsumer Devices,” filed Jul. 17, 2012.

U.S. patent application Ser. No. 13/551,563, “Home Network of ConnectedConsumer Devices,” filed Jul. 17, 2012.

BACKGROUND

Low-power, personal area networks such as ZigBee, Z-Wave, Insteon,JenNet-IP, X10 or similar are becoming increasingly prevalent.Appliances, lighting, heating and cooling, security and monitoringsystems, entertainment systems, communications, lawn sprinklers, etc.,now include control microprocessors and wireless communication devicesto allow for wireless connection to the home network. This allowscontrol of these devices to reside in smartphones, PDAs, laptopcomputers, desktop computers or other devices on which a user-friendlysoftware control interface exists, or control may reside in a networkcloud, with the only the interface being local.

Several different ways exist to organize and configure these networks.Existing technologies can associate the home devices into groups basedon the ability to communicate using visible light, ultrasound, infraredlight, radio frequency and other communications technologies, enablingthe devices to be organized into clusters based on the confined space inwhich they reside, as well as the kind of devices they represent.Integrating a microprocessor into the individual devices allows thedevices to receive programming that enables a high degree of flexibilityfor the user. However, the large number of available configurations canoverwhelm the typical user.

Most of the network technologies used here are relatively complicatedand difficult for the consumer to use. Adding, authenticating andconfiguring new devices and types may involve hiring a trainedtechnician to carry out the installation. As the costs ofmicroprocessor, memory, displays, radio transmitters and receivers andline of sight communications decrease, the cost of adding thesecapabilities to inexpensive and even disposable consumer productsbecomes possible. This will lead to a new set of challenges for theconsumers and the networks.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an embodiment of a consumer product device.

FIG. 2 shows a block diagram of an embodiment of a communicationsportion of a network device.

FIG. 3 shows an embodiment of a lighting device.

FIG. 4 shows an alternative embodiment of a lighting device.

FIG. 5 shows a diagram of an embodiment of a structure having multiple,potential nodes in an ad hoc wireless network.

FIG. 6 shows a flowchart of an embodiment of a method of building a roomlist.

FIG. 7 shows a flowchart of an embodiment of a method of assigning afunction to a room.

FIG. 8 shows a flowchart of an embodiment of a method of determining andexecuting an action based upon a configuration of an ad hoc, wirelessnetwork.

FIG. 9 shows a flowchart of an embodiment of a method of developing athree-dimensional representation of a house.

FIG. 10 shows an example of a three-dimensional representation of nodesin a structure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

General Node and Non-Lighting Device

FIG. 1 shows an embodiment of a consumer product device having networkcapability. The device 10 has a receiver or adapter 12 that contains aconsumer product. The consumer product may be one of many things. Forexample, the consumer product may consist of a consumable productdispenser that dispenses or delivers some type of consumable productsuch as shaving cream, air freshener, toothpaste, lotion, shampoo,cotton swabs, razor blades, tissue, etc. The consumer product mayconsist of non-powered implements such as a razor, a toothbrush, a hairbrush, a duster, a broom, a mop, a scrub brush, a toilet wand, etc. Theconsumer product may consist of powered devices, such as a coffee makeror other kitchen device like a toaster over, a television, a hair dryer,a vacuum cleaner, air purifier, humidifier, etc. These are only intendedas examples of both non-powered and powered products, no limitation toany particular product or configuration is intended nor should any beinferred. Consumer products, as defined here, do not have any networkingcommunication capability. Communication on these devices would only takethe form of local communications, such as user interfaces, warninglights, etc.

The receiver 12 would snap onto or allow the consumer device to beotherwise connected mechanically and possibly electrically to theconsumer product device 10. For powered devices, the receiver 12 mayinclude a standard 2 or 3 pronged receiver such as seen in poweroutlets.

The consumer product device also includes at least one communicationmodule or hub 14. The communications hub may comprise one communicationmodule, or several communication modules, each using a different type ofcommunication technologies. For example, the communication module mayconsist of a room-limited communication module. “Room-limited” meansthat the communication medium of this device uses signals that generallydo not penetrate barriers such as walls, floor and ceilings. Examplesinclude line of sight signals such as optical and acoustic signals. Thecommunication modules may also consist of, or include, aroom-transparent communication module. “Room-transparent” means that thecommunication medium of the device is not limited by walls and floors.These barriers may lessen the signal, but they generally do not stop it.The communication hub 14 may contain one or both of these types ofmodules, and may contain more than one of each type, such as tworoom-limited modules and one room-transparent, etc. each with its owncapability to connect to other devices in an ad hoc mesh network.

The network capability allows devices that would not otherwise have theability, to join and leave an ad hoc mesh network and communicate withother devices that may also not otherwise have that ability. Providingthese devices and products the ability to communicate and coordinatewith other devices allows the user to manage many aspects of his or herhousehold.

The consumer product device may also include a power connector 16electrically coupled to the communication module. The power connectormay take many forms, but will typically consist of a standard 2 or 3pronged plug. The power connector provides power to the communicationmodule and may also provide power to the consumer product portion of thedevice.

Other variations and modifications to the consumer product device arepossible. For example, a sensor 18 may allow the user to track a levelof consumable product within the receiver 12. For example, if theconsumer product consists of a dispenser of some sort, the sensor may bea light sensor. The light sensor could be positioned such that light tothe sensor is blocked by the consumable product. When the consumableproduct is used up, light would reach the sensor, indicating that thedispenser is nearly empty. Other types of sensors may include heatsensors, weight sensors, accelerometers, diagnostic sensors, air qualitysensors, VOC (volatile organic compounds) sensors, etc. Using thenetwork capability of the device, detection of the state of theconsumable product may trigger actions that will be discussed in moredetail later.

FIG. 2 shows an embodiment of the communication module 14 that providesthe network capability. The module may contain a room-transparent module26. The room-transparent module may be a radio, in which case it mayhave an associated antenna 22. The radio may communicate by way of oneof many different types of protocols, but will more than likely use apacket-based protocol such as the Internet Protocol. Even moreparticularly, the protocol may be one of IP version 6 (IPv6), such asIPv6 over Low Power Wireless Personal Area Networks (6LoWPAN), or theNeighborhood Exchange Protocol.

FIG. 2 shows both a room-transparent and a room-limited communicationmodule, with the understanding that only one is necessary to provide thenetworking capability. As mentioned previously, the room-limitedcommunication module will generally consist of a light of sightcommunication module, such as infrared light, visible light, andultrasound or other acoustic signals, etc. When a receiver is not withinsight of the transmitter, the receiver will not receive the signal. Theline of sight communication module may have an emitter such as 24coupled to it.

The communication module 14 will typically receive its power from apower outlet or battery through the power connector 16. However, thepower connector 16 may also consist of a wireless power receive. In someinstances, a base device may transmit a signal to a receiver that canconvert the signal into power for the receiver. Currently, these typesof receivers have very limited functionality because of the limitedamount of power they receive, and limited range due to losses in thesignal carrying the power. However, one can envision solutions to theseproblems being available in the future and the embodiments here are notlimited to direct power connections. Additionally, the device mayinclude both of these types of power connectors. The device may beconfigured such that the communications modules have extended range whenconnected to power.

Other optional components are of course possible. For example, thememory 20 may reside within the communication hub, within eachcommunication module, elsewhere in the device, or being a networked orremote memory such as is common in cloud computer. A controller 20separate from the communication module may also exist, each module mayhave its own controller, with a central device controller separate fromthose, or a networked controller.

In addition to sensors configured to sense the state of the consumableproducts, other types of sensors may exist on the device, or the sensormay reside on its own node. The sensor may be a security sensor, a radiofrequency identification tag, a barcode reader, or an environmentalsensor, motion sensor, sound sensor, odor sensor, smoke alarms, airborneparticulates sensor, pollen and dust sensor, air purification system,metrology, airborne biological agents sensor, bacteria and virusessensors, surface borne contaminants sensors, sanitary sensors, waterquality sensors, moisture sensors, etc. Environmental sensors may senseair quality, light level, temperature and air flow. For example, asensor sensing the air quality may determine that the room needsfreshening and can send a signal through the network to the airfreshener to freshen the air. For lighting applications, the sensorcould send information about the light level that would cause one ormore of lighting devices to turn on. Lighting devices as nodes will bediscussed in more detail later.

Returning to FIG. 1, the communications module may also have an optionaldirect connection communications port, such as a USB or IEEE 1394(Firewire) port 17. This may provide the user the ability to connect thedevice to a computing device for initial set up or programming, upgradesof firmware or software, as well as allowing the device to be directlyconnected to a consumer device having a similar port, such as atelevision or music system. The port 17 may also allow connection to anetwork access point or gateway to provide connection to an externalnetwork like the Internet.

Lighting Products

The discussion to this point has focused on consumer products other thanlighting products, including both light bulbs, which are any type oflighting item that screws into a socket to receiver power when switchedon and may include traditional incandescent bulbs, LED bulbs, compactfluorescent (CFL) bulbs, etc., and other lighting products such aslamps. And new forms of light that may obtain power through alternativemeans such as battery, induction, sonic etc. FIG. 3 shows an embodimentof an adapter 30 to be used with a light bulb. The communications module14 is part of a housing where the housing has a light emitter receptacle32 configured to accept a light bulb. This allows use of typicalhousehold light bulbs, rather than bulbs that have expensive adaptersalready in them, referred to here as fully integrated light bulbs, orspecialized sockets having centrally controllable processors and otheradapters. Fully integrated light bulbs with room lists and Ids.

Alternatively, the light emitter receptacle 32 could take the form of aplug in adapter similar to a power outlet, as shown in FIG. 4. In thisembodiment, the back side of the adapter would like similar to the backside of the adapter shown as 16 in FIG. 1. The communication module 14will have one or both of the room-limited communication module and theroom-transparent communication modules discussed in detail above. Thelight emitter receptacle could accept a light bulb, a light or lamphaving a power cord, or a light having an integrated power connectorsuch as that seen in emergency lighting for example.

Similar to the non-lighting adapter discussed above, the lighting devicemay also include a sensor. The sensor would typically consist of a lightsensor, but may also consist of a temperature sensor, a smoke detector,etc. The sensor may communicate with a controller resident in theadapter 30, or it may communicate with a controller located on otherlighting devices or non-lighting devices in the ad hoc network. Thecontroller may control the power connection, switching power to thelight emitter on or off as dictated by inputs from the sensor, possiblycombined with user inputs on lighting levels desired for particulartimes of day or activities.

The lighting device may form an ad hoc mesh network, in which devicesenter and exit the network at will, and all devices in the network maycommunicate with any and all devices within its range. While there maybe a central controller, each device may also have its own controller.Instead of a central controller, one device may designate itself as amaster node and provide control signals to the other nodes. Inaccordance with known ad hoc mesh network protocols, a node maydesignate itself as a master node, typically based upon its ability tobridge ad hoc mesh network to other networks. In the absence of such anode, the nodes will arbitrate who is the master. The specifics of theseprocesses are not the focus of the discussion.

The discussion to this point has focused on providing consumer productswith an ability to form ad hoc, wireless mesh networks. The consumerproducts may have intelligence ranging from relatively ‘dumb’ such aslight bulbs, sweepers, air fresheners, etc. to high sophistication, suchas in consumer electronics and computing devices. Having networks ofdevices with these capabilities may allow a user to segment the nodes ofthe network into rooms of the house or structure without any priorknowledge of its floor plan.

Room List/Room ID

FIG. 5 shows an example of a floor plan of a house. The techniquesemployed here may apply to any structure, such as an office building,hospital, that has more than one room. This discussion, focusing onconsumer products, will use a house as an exemplary structure. Nolimitation from this selection was intended or should be implied. Thenodes in this network reside in the rooms, but the user does not need orhave the floor plan. One should note that the user of the techniques andembodiments is not necessarily a human consumer. The ‘user’ may be acomputing device employed by a human consumer to gather this informationso that the human does not need to do so.

FIG. 6 shows a flowchart of an embodiment of a method of determiningwhich nodes reside in which rooms. At 40, the ad hoc mesh network isformed. This may involve deploying the nodes and then having thembroadcast signals notifying any nodes in the area of their presence. Thenodes may be lighting products or consumer products such as thosepreviously discussed. As part of forming the network, the nodes may sendout their signals and determine the presence of other nodes.

At 42 the signals between nodes are analyzed where the analysis mayoccur in several locations such as in the network, in the node, in thecloud. Referring to the floor plan of FIG. 5, some nodes will see nodesthat other nodes cannot ‘see,’ where ‘seeing’ a node means detecting thepresence of the node. For example, node I may see nodes J, A, and H.However, node J may also see node L and node K. Node K can see node M.By analyzing the signals, one can determine that node J cannot see nodeM, so a wall must exist between nodes J and M. Similarly, Node I can seenode H through the doorway, but node I cannot see node G, even thoughnode I knows of the existence of node G through information from node H.

Beyond this analysis, the nodes can also determine distances betweenthemselves. A receiving node can determine the time of a transmissionfrom another node and from that determine the distance between nodes,although not necessarily the orientation. Using these two types ofanalyses, as examples, one can determine rooms within a structure.Relying on the line of sight data, one can segment the nodes into rooms.Even further, relying upon the received signal strength, the network maybe able to determine approximate dimensions of the rooms. The nodes havemultiple ways of detecting each other, such as optically, electrically,using sensors, etc.

The above analysis assumes only the use of a room-limited communicationmodule. In some embodiments, the nodes may also use a room-transparentcommunication module. In this instance, the nodes may identifythemselves without relying upon room-limited communication. By couplingthis data with the line of sign data, the network can identify walls andopenings between nodes and segment the nodes into rooms at 44. Forexample, referring to FIG. 5, node I may be aware of the existence ofnode C based upon the room-transparent communication module. However,looking at the room-limited signals, node I would not be able to detectthe presence of node C, indicating a wall or other barrier lying betweenthem.

Once the nodes are segmented into rooms, the node information is updatedto associate that node with that room at 46. One of the nodes on thenetwork may include nonvolatile memory, or the nonvolatile memory mayreside external to the network, but in communication with one of thenodes. The room list and nodes associated with the rooms may be storedin this memory. The node upon which the nonvolatile memory or has thelink to the nonvolatile memory may be a master node as previouslydiscussed. As these nodes may be attached to or involve consumerproducts that may either be moved by a user or may themselves be mobile,this process may be repeated periodically to acquire updatedinformation.

One should note that while the above process concentrates on thesegmentation of the nodes into rooms, it is possible to also segment thedevices into other types of segments, such as segmenting them by user,type of device, etc. This discussion focuses on the segmentation byroom, but the use of other types of segments should be considered withinthe scope of the embodiments presented here.

Room Purpose

Once the nodes are segmented into rooms and the nodes associated withthose rooms, the network can determine a purpose for each room. FIG. 7shows a flowchart of an embodiment of a method of assigning a purpose tothe room. Processes 50-56 mimic those of FIG. 6 with similar if not thesame analysis of the signals to segment the nodes into rooms. The nodesform the network at 50, and the signals between the nodes are analyzed.As mentioned, the analysis may occur at each individual node, at amaster node, if one is designated, in the network, in the cloud, etc.Having segmented the nodes into rooms, the network would then obtain theidentity of one of the nodes in the room at 58.

Obtaining the identity of one of the nodes in the room may take manyforms. The nodes themselves may have information they encode into thesignals they transmit, such as a device identifier, a name, etc. Theuser could install this information into the node when activating thenode, using the USB port or a resident interface on the node. The nodewill have this information in what will be referred to here as ‘nodedata.’ The node data includes any information about the node, such asthe type of device at the node, the device state such a full or nearlyempty, its power status, what other nodes to which it is connected, etc.

In one embodiment, the node data consists at least of an identifier forthe device residing at the node. The node or another node on the networkaccesses a database of identifiers and uses the device identifier as anindex into the database. The resulting information provides the networkwith more information about the node. For example, the device may haveas an identifier a stock-keeping unit (SKU) number. Accessing a databaseresults in the SKU being identified as a toothbrush. Other types ofidentifiers may also exist. The identifier may be a bar code, a networkaddress, a presumed identity based upon an analysis of surroundingdevices or information about the environment, etc. Based upon thisinformation, the network may assign a room function to the room at 60,in this example in which the toothbrush resides as a bathroom.

The database may also take many forms. It may be a fully populatedproduct database, or merely a small look up table, and any conceivableoption in between those extremes. The database may reside in nonvolatilememory on a node in the network, or it may reside external to thenetwork but accessibly through a link to the external network.

Accessing the database may also occur in layers. A first database mayidentify a particular device as a toothbrush, triggering access of asecond database that provides more information about the toothbrush,such as a model number or brand name. In one embodiment, the databaseaccessed may consist of a database populated by consumers who havesimilar networks and may have better insight into assigning the functioninto the room.

The database may be organized in many different ways. In one embodiment,a table of nodes, a table of rooms, and associations between the tableof nodes and the table of rooms. In another, a table of nodes in thewireless network, a table of rooms in the house, a list of roomfunctions, and associations between the room functions, the rooms, andthe nodes.

In one embodiment, information contained in the room list may proveuseful in assigning a function to the room. If the room list were storedusing the identity to assign a function to the room based could be basedon a current room list. Alternatively, the room function could beassigned based upon a historical or previous room list, a current nodefunction list, a historical node function list, current node locationdata, historical node location data, current sensor data, historicalsensor data, user preference data, an external database of roomfunctions, blueprints of the home, and external data related to thehome.

Actions

Having identified a purpose for the room, the network may have thecapability to take action based upon the room purpose and the nodes inthe room. An embodiment of this process is shown in FIG. 8. In oneembodiment, at 62 the network has a node associated with a consumerproduct, such as an air freshener dispenser, with the understanding thatthe node may be associated with any type of consumer product device asdiscussed with regard to FIG. 1. In addition, the network has a nodewith a computing device such as node A, having a link to either aninternal or external network.

At 62, the consumer product node sends data to the computing devicenode. This data is node data, discussed above, and may include anidentifier of the node, a state of the consumer product, power status,etc. The computing device would then access a database at 64 to gathermore data about the node and associate that data with the node data. Thecomputing device can then make a determination of an action to be takenwith regard to the device at the node at 66 and execute that action at68. The action may be internal or external to the network.

Internal actions may involve altering the function of then node, such asshutting it down, slowing it down, reducing its usage, etc. It mayinvolve partner devices to the current node having their operationaltered, such as activating another device if one is running out ofsupplies. It may also involve updating an internal database, such as ashopping list to be provided to a user identifying supplies needed at aparticular node, or sending a message to the user within the network.

External actions may involve sending a text message to a user through alink to a cell phone network, sending an email through an Internetgateway and mail client, accessing an e-commerce gateway to order moresupplies, or accessing information about the devices residing at a nodefrom an external database.

For example, assume the node has an air freshener dispenser. The nodedata includes an identifier identifying the device as an air freshenerand a status indicating an amount of freshener remaining in thereservoir. The node transmits this data to the computing device. Thecomputing device accesses a database, either internal or external, anddetermines that based upon that amount, the reservoir is nearly empty.The database in this instance may merely be a list stored in a memory.The computing device then identifies different actions based upon thereservoir being nearly empty. The device could contact the user tonotify the user of the status. The device could access an e-commercegateway and order more air freshener. The device could also shut the airfreshener down to avoid burning the air freshener device out.

The selection of the action to execute may involve inputs from sensors,user inputs, previous conditions set by the user, etc. For example, asensor may detect that an air flow through an air filter has droppedbelow a particular threshold, indicating that the filter needs to becleaned or changed. This information would assist in the networkselecting the action to take.

In this manner, the network gains valuable knowledge about the devicesat the nodes of the network, allowing the network to provide services tothe user automatically. The more tasks and services the network canhandle, the easier it makes the use of the products and the network forthe user. Other benefits may also arise from having such a networkexisting in a structure.

Home Discovery

Mentioned above with regard to the layout of the structure, the user maynot have blueprints or floor plans available to input to the network.However, the nodes of the network may ‘see’ the structure differently.One benefit of the network may lie in its ability to develop athree-dimensional representation of the structure.

FIG. 9 shows one embodiment of a method of performing ‘home discovery’in which the network of devices generates a three-dimensionalrepresentation of the house. At 80, the network is provided that has atleast three nodes. The use of three nodes allows the one node totriangulate its position relative to the other two nodes. Generally, thecommunication modules in these nodes will be the room-transparentmodules. Having three nodes provides enough information for the signalanalysis and as one of the nodes may reside on a different floor, theroom-limited modules would not allow another node to see that node.

Using time of flight of the signals between the three nodes, as shown inFIG. 10, the signal analysis can produce a general layout of the nodeswithin a structure. In addition to the signal analysis, otherinformation may also exist. The type of node and whether the node ismobile may also be helpful.

For example, one of the nodes may attach to a floor sweeper, such as aSwiffer® dust mop. The movement of the floor sweeper when being usedprovides information as to where the non-carpeted floors exist, as wellas providing more triangulation data as to the location of the other twonodes. In another example, the node may be attached to a robotic vacuum,such as a Roomba®. This would allow identification of the carpetedsurfaces, as well as possible information about locations of furniturein rooms. Other mobile nodes are of course possible. The user could evenuse a duster or other type of ‘wand’ structure and map out the structurefor the network. Yet another alternative would involve attaching a nodeto a pet.

More information results in a more accurate picture of the house. Whilethe above discussion focuses on the use of the room-transparentcommunication module as a means of locating the nodes. However, theabove discussions also include the possibility of using the room-limitedmodules, as well as room segmentation and room purposes that havepreviously been identified. All of this information may be used togenerate a three-dimensional representation of the house, as well as thesignal analysis. This information would be stored within the network orexternal to it, but accessible by at least one node.

The above embodiments provide a convenient, simple and easy to use wayfor a user to establish a network of nodes of consumer products in ahome. The network gathers information for the user, or may act moreautonomously. The end result is a network of devices that will assistthe user in maintaining and enjoying his or her home.

It will be appreciated that several of the above-disclosed and otherfeatures and functions, or alternatives thereof, may be desirablycombined into many other different systems or applications. Also thatvarious presently unforeseen or unanticipated alternatives,modifications, variations, or improvements therein may be subsequentlymade by those skilled in the art which are also intended to beencompassed by the following claims.

What is claimed is:
 1. A method of generating a representation of astructure including at least two separate rooms, comprising: providingan ad hoc mesh network having at least two nodes associated with thestructure, wherein the nodes have at least two different communicationmodes; providing at least one consumer product within the structure, theconsumer product associated with at least one of the nodes; obtainingtime of flight data for each node in the network, wherein obtaining thetime of flight data comprises obtaining time of flight data for the atleast two different communication modes; using the time of flight datato generate the representation of the structure.
 2. The method of claim1, wherein the representation is a three-dimensional representation ofthe structure and the network has at least three nodes.
 3. The method ofclaim 2, wherein the node associated with the consumer product containsa sensor.
 4. The method of claim 1, wherein the node associated with theconsumer product is mobile and the time of flight data is obtained whilethe node is moving.
 5. The method of claim 4, wherein the nodeassociated with the consumer product is only used in a particular regionof the structure.
 6. The method of claim 5, wherein the consumer productcomprises a sweeper used only on non-carpeted floors.
 7. The method ofclaim 5, wherein the consumer product comprises a robotic cleaner thatavoids furniture and walls.
 8. The method of claim 4, wherein theconsumer product comprises a node attached to a pet.
 9. The method ofclaim 4, wherein the mobile node comprises a device arranged to becarried by a user to provide data with regard to the structure.
 10. Themethod of claim 1, wherein the step of providing an ad hoc mesh networkcomprises providing an ad hoc mesh network having at least four nodes.11. The method of claim 10, wherein using the time of flight datacomprises using the time of flight data for a fourth node to fix theposition of a third node to a point.
 12. The method of claim 1 furthercomprising using available data with regard to placement of nodes intothe rooms.
 13. The method of claim 12, further comprising usingavailable data with regard to purposes of the rooms.